Fix: Prevent contact count label from truncating (#4269)

[Icedmist]

Fixes #4269. The flex-shrink property allows the contact counter wrapper to shrink below its intrinsic width when the sidebar is constrained, causing the counter to truncate its contents. Added flex-shrink: 0 to prevent the truncation.

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Codecov Report

✅ All modified and coverable lines are covered by tests.

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